Mobile fire fighting apparatus



June 27, 1944. 5 GEERTZ MOBILE FIRE FIGHTING APPARATUS Filed Aug. 14, 1941 ll Sheets-Sheet l June 27, 1944.

E. GEERTZ MOBILE FIRE FIGHTING APPARATUS ll She ets-Sheet 2 Filed Aug. 14 1941 'Em'c Geertz;

June 27, 1944. E -rz 2,352,379

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June27, 1944.

E. GEERTZ MOBILE FIRE FIGHTING APPARATUS Fil'ed Aug. 14, 1941 11 Sheets-Sheet s Eric 6862212 lllr ll I I June 27, 1944. E. GEERTZ 7 MOBILE FIRE FIGHTING APPARATUS Filed Aug. 14, 1941' ll Sheets-Sheet 7 June 27, 1944. E, GEERTZ 2,352,379

MOBILE FIRE FIGHTING APPARATUS Filed Aug. 14, 1941 ll Sheets-Sheet 8 Eric Geeriz June 27, 1944. E. GEERTZ Mopm: FIRE FIGHTING APPARATUS Filed Aug. 14, 1941 11 Sheets-Sheet 9 Geertz 3mm Eric MQN 90M 3 NOD J ll Sheets-Sheet 10 I; eer tz QWN Filed Aug. 14, 1941 E GEERTZ MOBILE FIRE FIGHTING APPARATUS June 27, 1944. a. GEERTZ 2,352,379

MOBILE FIRE FIGHTING APPARATUS Filed Aug. 14, 1941 ll Sheets-Sheet ll I! lmlllllllil lW/Z/AIllil l-mm extinguishing apparatus.

Patented June 27, 1944 MOBILE FIRE FIGHTING APPARATUS Eric Geertz,- Glen Ellyn, Ill., aslignor, by mesne assignments, to Reconstruction Finance Corporation, Chicago, 111., a corporation of the United States.

Application August 14, 1941, Serial No. 406,890

31 Claims.

This invention relates to new and useful improvements in mobile fire fighting apparatus.

This application is a continuation-in-part of my application Serial No. 263,301, filed March 21, 1939, for Mobile fire fighting apparatus, which in turn is a continuation-in-part of the application which has matured into Patent No. 2,202,343, issued May 28, 1940.

The primary object of this invention is to provide self propelled trucks which are so equipped as to adapt the same for use as self-contained, combined liquid carbon dioxide and water fire Due to the flexibility oi the apparatus, they are especially adapted for use as fire and crash trucks at aviation flying fields and as fire trucks for storage yards of coal, lumber, grain, highly inflammable fluids, etc., and for manufacturing plants, freight yards, trash dumps, rural communities, and the like.

A further highly important object of the in Q vention is to provide mobile fire fighting units which may be employed for transporting to the immediate vicinity of a fire'a substantial volume of liquid carbon dioxide which has been maintained at a desired low temperature and corresponding vapor pressure awaiting use.

Another object of the invention is to provide mobile fire fighting units which,with the exception of beingsupplied with electricity from an external source while standing idle at their accustomed places of, storage, are self-contained to the point of being able to discharge onto a fire, located either in the immediate vicinity of or at a considerable distance from said place of storage, a large quantity of liquid carbon dioxide confined at a temperature and its corresponding vapor pressure which may be any desired number of degrees below that of the surrounding atmosphere, so as to provide a type of discharge which will include a high percentage 01' snow, and/or a considerable quantity of water to be expelled by the vapor pressure of the carbon dioxide.

.A still further object or this invention is to provide self propelled fire fighting units which are equipped to permit one operator to drivethe unit to the scene of the fire and to direct 'a stream of carbon dioxide gas and snow onto and around the fire through a dirigible discharge nozzle without having to leave the position of the driver's seat.

Still another object of the invention is to provide mobile fire fighting units, which include equipment adapted to be supplied with electricity from a fixed source located at the accustomed places 01 storage for the units, with quick, self breaking electric connections which will enable the units to be driven away from said places of storage without requiring previous attention or in any way damaging the connecting mechanism.

Another object 01 the invention is to provide mobile fire fighting units with one or more nozzles which are adapted for being manipulated from the driver's seat of the unit for varying the direction of discharge from the nozzles in both vertical and horizontal directions without necessitating moving the unit.

It is a still further object or the invention to provide mobile fire fighting units which are capable of carrying to the immediate vicinity oi. a fire a large quantity of low temperature and pressure liquid carbon dioxide and a considerable quantity of water to be expelled by the vapor pressure of the carbon dioxide and, by means of one or more suitable combination discharge devices and controls, efiect simultaneous discharge of the same as mixtures of carbon dioxide snow and vapors and water particles with the result that the eflectiveness of the low temperature carbon dioxide to extinguish certain types of fires will be improved, the amount of carbon dioxide required to efiect extinguishment will be reduced, and the carrying and penetrating character of the low temperature carbon dioxide will be increased to a considerable extent beyond any values which can be obtained when the carbon dioxide constitutes the sole extinguishing medium discharged.

Other objects and advantages of the invention will be apparent during the course of the following description.

In the accompanying drawings forming a part or this specification and in which like numerals are employed to designate like parts throughout the same,

Figure 1 is a side elevational view of the mobile fire fighting unit embodying this invention,

Figure 2 is a top plan view of the unit illustrated in Fig. 1,

Figure 3 is a side elevational view of the fire extinguisher medium handling equipment for the unit disclosed in Figs. 1 and 2 with the remain ingv parts of the unit removed to better illustrate the fireextinguishersystem,

Figure 4 is a top plan view of the mechanism disclosed in Fig. 3,

Figure5 is a detail elevational view of electrical connecting mechanism employed for supplying certain elements of the unit with electricity and being designed to permit the unit to be driven away from the fixed source of supply without preliminary attention,

Figure 9 is a vertical sectional View taken on I line 9-9 of Fig. 8,

Figure 10 is a side elevational view of a mobile fire fighting unit of the general type disclosed in detail in Figs. 1 to 4 inclusive but with a modified form of dirigible discharge apparatus mounted on the top of the vehicle body and manipulated encloses the major portion of the fire flghtinz equipment. The rear end of the body I is provided with a step or platform I6 for additional firemen and a suitable hand rail I1 is carried by the body II) for the convenience of the occupants of the step or platform I6.

As additional miscellaneous equipment, the unit is provided with a Searchlight III, a fire siren I, a plurality of hand fire extinguisher units 2., doors 2| for the drivers cab I3, and doors 22, 23, 24, and 25 mounted in opposite sides of the shell or sheathing I! to permit access to be had to the equipment housed by said shell.

and controlled by an operator located on a plat- I form extending across the top of the vehicle body,

Figure 11 is a top plan view of the embodiment of the invention disclosed in Fig. 10,

Figure 12 is a diagrammatic view of the control mechanism of the discharge apparatus illustrated in Figs. and 11,

Figure 13 is a detail vertical sectional on line I3-I 3 of Fig. 12,

Figure 14 is a detail elevational view of a water discharge ring which forms an operative part of the discharge nozzle shown in Figs. 10 to 12. inclusive,

Figure 15 is a partial side elevational view of a mobile fire fighting unit ofthe general character illustrated in detail in Figs. 1 to 4 inclusive and illustrates a still further modified form of dirigible view taken discharge mechanism which is mounted on the top of the vehicle body and which may be controlled from either the drivers cab or a'location on the top of the body,

, Figure 16 is a top plan view of the unit shown in Fig. 15,

Figure 1'7 is a partly front elevational view and partly diagrammatical view of the unit shown in Figs. 15 and 16 and is intended to more specifically illustrate the discharge mechanism,

Figure 18 is a diagrammatic view of the control mechanism for either one of the boom type of discharge devices disclosed in detail in Figs. 15 to 17 inclusive,

Figure 19 is a detail, elevational view of the swivel mounting employed for supporting one of the discharge booms illustrated in Figs. 15 to 17 inclusive,

Figure 20 is a detail top plan view of the swivel mechanism shown in Fig. 19, and

Figure 21 is a detail vertical sectional view taken on lines 2 I-2 I of Fig. 20.

In the drawings, wherein for the purpose of illustration is shown one preferred embodiment of this invention, and particularly referring to Figs. 1 and 2, the reference character I0 designates in its entirety the body of a self propelled truck which is supported by the ground engaging wheels II. While this unit is illustrated as being of a design best adapted for traveling over highways, and the like, it is to be understood that the unit may be provided with suitable rail engaging wheels so that it may be propelled along tracks and be a part of railway equipment. A suitable gasoline engine, or the like, not shown, is provided for the unit and is controlled by the driver occupying the seat I2 of the drivers compartment I3. An additional seat I4 may be provided in the compartment or cab I3 for a second fireman. The remainder of the body Ill takes the form of a suitable shell or sheathing I5 which Located within the shell I5 is a tank 26 which is adapted for receiving liquid carbon dioxide. This tank should be capable of storing two tons of carbon dioxide and should possess sumcient strength to confine the carbon dioxide at low pressures; for example, 500 pounds or pounds per square inch, in view of certain devices which are included as a part of the equipment of the unit. This liquid carbon dioxide storage tank is completely enclosed in a heavy covering oi insulating material 21 to prevent to the greatest extent possible the absorption of heat by the carbon dioxide stored within the tank. This storage tank and insulation covering assembly is arranged to extend longitudinally of the body III so as to be centered with respect to the width of the body and with its center of gravity located slightly in advance of the axle for the rear ground en gaging wheels.

Liquid carbon dioxide is adapted to be dispensed from the storage tank 26 through the hose line 28 which is carried by a suitable reel 2' mounted within the shell I5 of the body in the space provided between the rear end of the tank 26 and the rear step or platform IS. The liquid carbon dioxide also may be discharged through the dirigible nozzle mechanism designated in its entirety by the reference character 36 and located at the front end of the body I0. The hose. line 28 and the dirigible nozzle mechanism 30 are cash provided with a suitable discharge head or nozzle tip 3|. These discharge heads or nozzle tips may dropping to the value where the carbon dioxide will solidify, approximately 75 pounds per square inch; to bring about a sufiicient drop in pressure within the discharge heads or nozzle tops to convert the carbon dioxide to a mixture of gas and snow, and to actually expel or project the mixture into the atmosphere at a desired velocity. Discharge heads or nozzle tips suitable for accomplishing these desired results are disclosed In my Patent No. 2,238,693, issued April 15, 1941, and in the patent of Harry Ensminger, No. 2,289,- 352, issued July 14, 1942.

- Access to the reel 29 with its hose line 28 may be had through the opposite side doors 25 or the body shell or housing I5. It will be appreciated that the discharge head 3| and the hose line 23 may be pulled out through either side opening closed by the doors 25.

A mechanical refrigerating unit, designated in its entirety by the reference character 32, is arranged in the space between the front end of the carbon dioxide storage tank 26 and the driver's compartment I3. This refrigerator unit, as will be fully explained at a later point, is employed for automatically maintaining the temperature of the liquid carbon dioxide stored within the tank 26 at any desired value below that of normal room or atmospheric temperature. The advantages of employing liquid carbon dioxide, maintained at a sub-atmospheric temperature and its corresponding vapor pressure, as a fire extinguishing medium, are fully disclosed in my'Patent No. 2,143,311, issued January 10, 1939. Briefly stated, .the use of liquid carbon dioxide maintained at a sub-atmospheric temperature and pressure produces a much higher percentage of yield of snow when discharged to the atmosphere than is possible with carbon dioxide stored at the higher temperature of the surrounding air and the storage tank may be filled to a much higher percentage of its total capacity than is permissible where the carbon dioxide in storage is subjected to and is maintained at the temperature of the surrounding air. It is preferred that the refrigerating apparatus 32 maintain the temperature of the carbon dioxide stored within the tank 26 either at or below 32 F. Probably the most generally satisfactory temperature is F. The vapor pressure of the stored carbon dioxide at this temperature will be approximately 290 lbs. gauge pressure.

Located above the refrigerating apparatus 32, in the space between the drivers cab I3 and the front end of the carbon dioxidestorage tank 26 is a second storage tank 33 which is intended to hold approximately 100 gallons of water. This storage tank may be filled through the manhole 34, located in the top of the body in. The water in this tank 33 is intended to be discharged through the hose line 35 carried by the reel 36 which is located within the-shell or housing I at one'end of and below the tank 33. Access to this hose line 35 may be had through the door 22 located at its side of the body I0. The displacement of the water from the tank 33 by means of the vapor pressureof the carbon dioxide stored in the tank 26 will b explained in detail at a later point.

Figs. 3 and 4 disclose in detail the mechanism of the unit employed for maintaining and expelling the liquid carbon dioxide and the water. These various devices will be described in detail in connection with these two figures.

It is preferred that the ,tank 26 be charged with liquid carbon dioxide at the temperature and pressure at which the carbon dioxide is to be maintained while in storage. The liquid carbon dioxide, therefore, is charged into the tank through the dome 31 of the-tank by means of the pipe line 38. This pipe line is provided with a control valve 39 and terminates in a suitable coupling end 46 at the side of the tank. T0 permit the liquid carbon dioxide to be pumped into the storage tank 26 from the source of supply of the liquid, the vapor pressure in the tank 26 and the tank which contains the source of supply should be equalized. This equalizing of the vapor pressure in the two tanks is accomplished by means of the pipe line 4! which ,extendsrinto the dome 31 and is provided with a control valve 42. The end of this pipe line terminates in a suit able coupling 43 located alongside of the supply line coupling 40. I

The discharge of the low temperatur and pressure liquid carbon dioxide from the tank 26 to the hose line 26 is by means of the T coupling 44, connected to the bottom of the tank 26, and the pipe line 45 which leads to the center of the hose reel 29, as at 46. A control valve 41 is provided in the pipe line 45. To enable the firemen using the hose line 28 to have final control of the discharg of the extinguishing medium, a control valve 48 is provided in the hose line, 26 adjacent the discharge head or nozzle tip 3|. Discharge of theliquid carbon dioxide through .the dirigible nozzle assembly 30, located at the front end of the unit, is through th T coupling 44 and the pipe line 49 to the coupling 56. From the coupling 50 down to the dirigible assembly 30, the liquid carbon dioxide is fed through a section of flexible hose or tubing 5|. A control valve 52 is located in the pipe line,49. Th portion of the pipe line 49 which includes the control valve 52 extends through the driver's cab or compartment l3 so that the control valve 52 will be conveniently located with respect to the occupants of either one of the seats 12 and I4,

see Figs. 1 and 2.

For the purpose of determining at a glance, from the exterior of the shell or housing II, the level of the liquid carbon dioxide within the tank 26, an electric liquid level gauge 53 is mounted on one of the doors 23 of the shell or housing i5.

7 Wires 54 connect the gauge 53 with suitable mechanism located within the tank, not shown, and these wires 54 xtend through a suitable outlet pipe 55 connected to the dome 31. Of course,

' this outlet pipe 55 must be constructed to permit the wires 54 to extend outwardly thereof without leakage ofpressure from within the tank 26. The reference character 56 diagrammatically designates a suitable mechanical liquid level gauge which may be employed if desired to supplement the electric gauge 53. No attempt has been made to illustrate mechanism for either of these gauges. As will be explained at a later point, this fire fighting unit is supplied with electricity from a fixed source while' the unit is at its accustomed place of storage. The electric liquid level gauge, therefore, will be entirely satisfactory during periods when the unit is not actually being used to extinguish a fire. While on a run," the unit is not supplied with electricity from an external source and a mechanical liquid level gauge is needed during actual periods of use of the unit. or course, th liquid level gauge 53 may be designed to operate from the storage battery which forms a part ofthe ignition system of the unit if such an arrangement is found to be desirable. Under such operating conditions, a mechanical liquid level gauge would only be needed as a supplement for the electric liquid level gauge in case of mechanical failure of said latter gauge.

For the purpose of maintaining the liquid carbon dioxide within the storage tank 26 at a desired sub-atmospheric temperature, and its corresponding vapor pressure, a suitable evaporator coil 31' is arranged within the dome 31 of the tank 26. Thisevaporator coil operates to condense the carbon dioxide vapors which contact the same. The condensate runs back by gravity to the body of liquid within the tank. The evaporator coil is connected at one of-its ends to one side of the compressor 51 by means of the compressor line 58. The other side of the compressor 51 is connected by a pipe line 59 to a radiator type of air cooled condenser 60. The remaining side of the condenser 60 is connected to a refrigerant receiver or storage tank 6|. A pipe line 62 extends from the receiver or storage tank 61 to the expansion valve 63 located above the dome 31 and connected by a pipe 64 with the second end of the evaporator coil located within the dome 31. This series of elements,

bearing reference characters 51 to 64, inclusive,

constitutes the circuit for the refrigerating apparatus. The compressor 51 is suitably driven by an electric motor 65.

The expansion valve line 62 has coupled therein a pressure filter 66 and a sight glass 61, which are best illustrated in Fig. 3. A thermobulb 68 is located in the compressor line 58 and is connected by suitable tubing 69 to the expansion valve 63. This bulb and tube provide a pneumatic control for varying the extent to which the expansion valve 63 is opened and responds to temperature changes in compressor line 53.

This refrigerating apparatus is intended to be automatically controlled so as to maintain the temperature of the liquid carbon dioxide within the storage tank 26 at a desired value. To obtain this automatic control, a mercury switch 10 is connected by a gas pressure pipe line 1| to a connection 12 which extends out of the top of the tank dome 31. This mercury switch is electrically connected in the circuit wires 13 for the electric motor 65. These circuit wires 13 extend to a terminal box 14, mounted on the side of the motor 65 and to a connector device 15 shovm in Figs. 1 and 2 as being mounted at the rear end of the shell or housing I for the body of the unit. r

A suitable pressure gauge 16 is connected in the gas pressure line 1|, extending from the tank dome 31 to the mercoid switch 10. With this arrangement, the refrigerator mechanism will be automatically controlled by the vapor pressure of the liquid carbon dioxide stored within the tank 21. When this vapor pressure rises above the desired value at which the mercoid switch is set to operate, the circuit for the refrigerator motor 65 will be closed and the compressor 51 will be operated. When the temperature of the carbon dioxide within the storage tank 26 drops to a point where the corresponding vapor pressure will again actuate the mercoid switch 10, the circuit for the refrigerator motor 65 will be broken and the compressor will be stopped.

It is desired to have the electric motor 65 of the refrigerating mechanism connected to a suitable source of supply of electricity while the fire fighting unit is located at its customary place of storage so that the temperature of the liquid carbon dioxide within the storage tank 26 will be maintained at the desired low value. It, also, is highly desirable to be able to quickly drive away the fire fighting unit without being called upon to first manually break the connection between the supply lines 13 of the refrigerator motor and the fixed source of supply of electricity.

Fig. 5 diagrammatically illustrates means forautomatically breaking this electrical connection without in any way damaging the equipment.

The connector box 15, which forms a part of the fire fighter unit, is adapted to make connection with a push plug 11 which is carried by a wire cable or cord 18. This electric cord or cable extends to a'rewind reel 19 mounted on a suitable wall 80 of the storage space for the unit. Electric cables run from the reel 19 in a suitable conduit 8! to a switch box 82, also mounted on the wall. This switch box includes a control arm 83 which is illustrated in Fig. 5 in the position assumed by the same when the switch within the box 82 is closed. A pull cable or cord 84 is connected at one end to the push plug 11 and at its other end to the switch operating arm 83. A safety cord or cable 85 is anchored at one end to the wall 80 and is connected at its remaining end to the switch operating arm 33.

When the fire fighting unit is driven away from the wall 80, the pull cord 84 will operate to move the switch operating and 33 into a position to open the switch within the box 32. The safety cable or cord 85 will limit the outward swinging movement of the switch operating arm 83. The pull cord or cable 84 and the safety cord or cable 85 will then function to pull out the push plug 11 from the connector box 15. This mechanism, therefore, operates to permit the fire fighting unit to be driven away from its accustomed place of storage without requiring any preliminary consideration or manipulation of the electrical connecting mechanism.

As has been stated heretofore, the water stored within the tank 33 may be expelled by employing the pressure of the carbon dioxide within the storage tank 26. To accomplish this desired result, the top of the water storage tank 33 is connected by means of a vapor pressure pipe line I to the connection 81 extending from thedome 31 of the carbon dioxide storage tank 26. A hand control valve 38 is positioned in this line 66.

If the fire to be extinguished by the unit is of such a character as to be best treated with water,

the valve 88 may be opened for creating any desired pressure within the water storage tank 33. The water from this tank, of course, is to be directed to the fire by means of the hose line 35 mounted on the reel 36. The withdrawal of gas from the vapor space of the carbon dioxide storage tank 26 will have no detrimental effect upon the liquid carbon dioxide stored therein. As a matter of fact, withdrawal of vapor from the storage tank 26 will operate to lower the temperature of the liquid stored therein.

The operator in charge of the fire fighting unit should possess suflicient experience or knowledge to be able to ascertain whether the particular fire being dealt with can be best extinguished by means of carbon dioxide or water. If carbon dioxide is to be employed, it may be discharged either through the dirigible assembly 30 at the front of the unit, or it may be discharged through the hose line 28 coming from the rear end of the unit. Of course. both of these discharge devices may be simultaneously employed if found to be necessary. If water will make a better extinguishing medium than carbon dioxide, the fire fighting unit is driven to the vicinity of the fire and the hand valve 88 is manipulated to build up a desired discharging pressure within the water storage tank 33. The hose line 35 is then employed for directing the water from the tank 33'on to the fire.

If the liquid carbon dioxide is employed in an endeavor to extinguish the fire and the supply of liquid carbon dioxide becomes exhausted before the fire is completely extinguished, the vapor or gas remaining in the carbon dioxide tank 26 may be employed for building up pressure within the water storage tank 33 so that the water can be used in an endeavor to finally extinguish the fire.

Should the fire fighting unit be compelled to remain away from its accustomed place of storage, with the source of supply of electricity, for an unusual length of time, or should the source of supply of electricity at the storage space for the unit fail for any reason, a dangerous pressure condition might arise within the storage tank 26. To fully protect the system from such a possibility, a pipe line 89 extends from the side of the dome 31 and connects with a branch pipe 90 which has mounted on its extremity a mounting 9| for a frangible disc, not shown. This disc will rupture or blow out upon the attainment of any predetermined pressure within the tank 26 If, for any reason, electricity cannot beobtained for operating the electric motor 65 of the refrigerating unit for a limited length of time. the desired low temperature and pressure ofthe liquid carbon dioxide within the storage tank 26 may be obtained by bleeding gasor vapor from the dome 31 of the tank 26 through a branch pipe 92, extending from the pipe line 89, and a pop valve 93. For supplementing the operation of-the pop valve 93, a safety valve 94 is also connected to the branch line 92. A three-way plug valve 95 controls communication between the branch line 92 and the pop and safety valve 93 and 94, respectively.

Referring particularly to Figs. 6 to 9, inclusive. there is disclosed the dirigible discharge assembly for the liquid carbon dioxide with its control mechanism. Projecting from the front end of the body I of the fire fighting unit is a frame which includes the two longitudinally extending bars 96 and the parallel, transversely extending bars 81 which are connected at their opposite ends to the longitudinal bars 96. A base plate 98 is suitably mounted on the transversely extending bars 91. This base plate 98 includes a main body portion which is of substantially circular formation, see Figs. 6 and 8, with a rearwardly extending flange portion 98a carried thereby. Fig. 9 discloses a central aperture 99 formed in the main, circular body portion of this base plate. A turntable, designated in its entirety by the reference character I00, is rotatably mounted on the circular portion of the base plate 98 and, preferably, is centered with respect thereto. This turntable I00 includes a circular base portion IOI which is recessed in its under surface to provide an annular channel I02. Received within this channel and'cooperating with the top surface of the base plate is a ball bearing assembly I03 which functions to rotatably support the turntable I00 on the base plate 98.

The turntable I00 is maintained in place by means of the shaft I04 which passes through the-aperture 99 formed in the base plate 98 and through an aperture I05 formed in the base IOI of the turntable. I05 is a bearing recess or pocket I06 which opens upwardly of the turntable base IOI. Positioned within this bearing recess or pocket I06 is a ball bearing assembly I01. The upper race member of this ball bearing assembly snugly fits the periphery of the shaft I04 and rotates with this shaft. The lower race remains stationary with respect to the turntable base IN. A bearing cap I08 overlies and closes the top of the bearing recess I06. This bearing cap has a central aperture I09 for the passage of the shaft I04 and an enlarged recess IIO for receiving the head III of the shaft. The lower end of the shaft I04 is reduced and externally screw threaded, as at H2. Threaded on this reduced portion is a nut II3. A washer H4 is interposed between the nut H3 and the lower face of the base plate 98. This nut II3 with the washer II4 ties the sh ft I04 to the base plate 98 and retains the turntable assembly in proper position.

Project ng u wardly from the base portion IOI of t e turntable are the two bracket arms II5 which are arranged in spaced parallelism. The

Concentric with the aperture A pipe saddle I20 'is journaled'on the spindle I IT. This pipe saddle includes a main body portion I2I which has the bearing'openings I22 at its opposite ends for rotatably receiving or fitting the spindle III. Projecting upwardly and laterally in opposite directions from the central portion of the main body I2I is a semi-circular pipe seat I23. The opposite end portions of this seat. are provided with laterally projecting ears I24..

The several figures clearly indicate that there are four of these ears I24. Each transverse pair'of ears 124 has secured thereto a pipe clamp I25 by means of the screws I26 which are threaded into the apertures of the ears I24.

Figs. 6 and '7 disclose the rigid pipe stern I28 as" being mounted in the seat I23 of the saddle I20 and as being retained in this seat by straps I25. This stem I28 for the discharge head or nozzle tip 3|, therefore, is securely fastened tothe pipe saddle I20.,

It is desirable to be able to adjust the discharge head 3I and its rigid stem I28 both horizontally and vertically, or by means of a universal joint type of support. The right angularly arranged shaft I04 and spindle III with the turntable I00 and the pipe saddle I20 form this type of mounting for the discharge head 3| and its pipe stern I28. For the most efficient operation of this dirigible discharge assembly, it is desirable that the discharge head and its stem be manipulated from the driver's seat I2 in the cab or compartment I3. The mechanism for accomplishing this result is clearly illustrated in Figs. 6 and 7.

The base IOI of the turntable I00 has projecting forwardly from its front side two ears I29. The periphery of the turntable base IOI is provided with semi-circular, cord receiving grooves I30. Cords or cables I3I are attached at their forward ends to the ears I29 and extend around the turntable base IOI within the grooves I30. cables I3I are brought around to the re'arwardly projecting flange 98a of the base plate 98 and cross each other through the two guideways I32 of the double clevis I33 which is mounted on the said flange 98a, see particularly Figs. '7 and 8.

The cables I3I then pass around sheaves I34 which guide them. up to the level of the bottom end of a control lever I35 which is universally mounted at I36 in the bracket I31. The opposite ex-I tremities of these cords or cables I3I are attached to the lower end of the control lever I35. By rocking this lever, through the medium of its handle I38, laterally in opposite directions, the turntable I00 with its supported discharge head 3| will be moved horizontally about the axis of the perpendicular shaft I04.

Depending from the opposite end portions of the pipe seat I23 are apertured ears I39. These apertured ears, as will be seen in Fig. '7, are

These of the control stick I35 and approach this control stick from opposite sides; 1. e., from the front and rear sides of the stick. These cords I40 are connected to the lower end portion of the stick I35 and movement of this stick forwardly or rearwardly will bring about rocking movement of the discharge head I'3I and its pipe stem I28 about the axis of the spindle I I1 for vertically changing the discharge from the head 3L.

From this disclosure of the control mechanis for the. discharge head 3| and theprevious description of the control valve 52 for the pipe line which leads from the bottom of the liquid carbon dioxide storage tank 26 to the discharge head II, it will be appreciated that one operator may drive this fire fighting unit up to the location of a fire and, without leaving the driver's cab I3, start and control the direction. of discharge of a stream of carbondioxide gas and snow on to the fire. As one portion of the fire is'quicklyextingui'shed by this discharge of carbon dioxide, the operator may quickly and easily change the location of the fire fighting unit for directing the extinguishing stream on to other portions of the fire. This combined control of the fire fighting unit and its .dirigible discharge assembly particularly adapts the unit for fighting a fire which is burning over a considerable area. I

The remaining figures of the drawings, identified by'the numbers to 24 inclusive, disclose three mobile fire fighting units which are modifications of the unit disclosed in detail in Figs. 1 to 9 inclusive. -To avoid unduly multiplying the drawings, the modified units of Figs. 10 to 24 inclusive'have been prepared so that they only illustrate the modified structures. It is to be understood, however, that these additional units are provided with the same equipment for maintaining asuitable source of supply of liquid carbon dioxide at a desired, controlled sub-atmospheric temperature and its-corresponding vapor pressureia source of supply of water which is to be expelledby carbon dioxide vapor pressure obtained from the storage unit for this latter medium, and a suitable hose line foreffecting discharge of the water when this extinguishing medium is to be used by itself. Figs. 10 and 11 disclose a hose line for effecting discharge of the carbon dioxide by itself for the unit shown in Figs. 10 to 14 inclusive. Figs. 22 and 23 also disclose this type of discharge for the carbon dioxide. The rear endof the unit illustrated in Figs. to 21 inclusive has been omitted but it is /to be understood that a hose line for the carbon dioxide is to be provided for this modification.

in Figs. 1 to 9 inclusive by employing modified forms of discharge mechanism and by providing for the discharge of an extinguishing medium which consists of a mixture of carbon dioxide vapors and snow with a suitable quantity of water particles entrained therein. The method of extinguishing fires resulting from combining carbon dioxide snow and vapors with water particles is fully disclosed and claimed in my Patent Numbered 2,248,270, issued July 8, 1941. Additionally, these three remaining modifications diifer from the embodiment of the invention illustrated in Figs. 1 to 9 inclusive by employing control mechanism for effecting this combined discharge of carbon dioxide and water.

The reference characters employed in Figs. 1 to 9 inclusive foridentifying certain structural elements of the vehicle body per se, etc., will be employed in Figs. 10 to 24 inclusive to identify,

the same elements where they are illustrated in the latter figures. New reference characters will only be applied to the elements which actually constitute the modifications. 7

Referring now specifically to the disclosure of Figs. l0to 14 inclusive, the reference character I44 designates in its entirety a rigid tripod which is suitably secured to the roof of the driver's cab I3. An oar-lock type of swivel mounting I45 is suitably attached to the upper end of this tripod. The arms ofthis oar-lock or fork I45 have positioned between the same the barrel I46. A pivot pin I41 is employed for attaching the barrel'to the swivel member I45. It will be appreciated. therefore, that the barrel I46 may partake of universal movement relative to the tripod I44. The movement about axhorizontal axis is provided by the pivot pin I41 while the movement about a vertical axis is provided by the mounting pin I46 which connects the swivel mount I45 to the tripod.

The rear or inner end of the barrel I46 has suitably attached thereto or formed thereon 'a pistol grip I49 with which is associated a trigger lever I50.

The outer or front end of the barrel I46 has suitably attached thereto a special elbow coupling I 5I provided with an angular bore I62 which communicates at one end with a pipe I54 that leads to a diflerential pressure operated valve casing I54. The remaining end of the elbow coupling bore I52 communicates with a pipe I55 which has suitably moun'ted'on its outer end the discharge nozzle I56. This discharge nozzle is of a suitable design to effect a dense discharge of carbon dioxide snow and vapors when low temperature liquid carbon dioxide is delivered thereto through the pipe I55, etc. The differential pressure valve 'casing I 54 has a second branch connected to a pipe line I51 which extends into the carbon dioxide storage tank '26 to terminate near the bottom thereof. A suitable manual control valve I58 is provided in this pipe line I51 and functions to either completely shut off the fiow of liquid carbon dioxide through the pipe line or to regulate the rate of flow.

The water supply tank 33 is connected to the vapor space of the carbon dioxide supply tank 26 by means of the pipe line 86 which is controlled by the manual valve 88. From the bottom of the water tank 33 extends a. pipe line I510 which is connected at its outer end to one branch of 'the fiuid pressure operated valve casing I56a. The remaining branch of this casing has a pipe section I59 connected thereto. A flexible hose I60 is connected to the outer end of the pipe section I59. This hose is secured to the pipe I55 by suitable straps I6I and extends to and is connected with a ring I62 which surrounds and is suitably secured to the periphery of the carbon dioxide discharge nozzle I56.

Fig. 14 discloses this water discharge ring I62 in detail. Radially inwardly directed ports I63 are formed in the water ring I62. When carbon dioxide is discharged through the nozzle I56 and water is discharged in the form of a plurality of jets through the ports I63 of the ring I62, the water jets or streams'will be thoroughly broken up by the carbon dioxide discharge so that all of the water particles will be entrained in the cloud of carbon dioxide snowand vapors. A complete explanation of the advantages and mode of operation of this type of combined discharge is fully set forthin my aiorementioned Patent No. 2',248,270'and reference may .be had thereto for a more thorough understanding.

In effecting control overthe simultaneous discharge of carbon dioxide and water, it is desirable for the operator to be able to control both of these fluids bymeans of a single element. The

trigger lever I50 is employed for this purpose. This lever has connected .thereto a cable I66 which passes around the sheave I65 and extends to the operating lever I66 of a pilotvalve I61. This lever is employed for unseating a spring loaded valve I68. Whenthis valve is unsated, the chamber of the pilot valve casing is placed in communication with the vent I69.

A pipe line I18 connects the chamber of the pilot valve casing I61 to' the cylinder I1I formed in the top of the differential pressure valve casing I56. A "second pipe line I12 connects the chamber of the pilot valve casing I61 to the carbon dioxide pipe line I51 in advance of themlet for the differential pressure valve casing in. I

When the valve I68 of the'pilot valve structure I61 is seated, the pipe linesfl18 and I1 2.deliver carbon dioxide to the cylinder I1I oi the differential pressure casing I54. This carbon dioxide applies pressure to the top surface of the piston operated valve I13 which is located in the dif ierentiai pressure casing I54. In other words, this piston of the valve I19 normally has carbon dioxide pressure applied to both of its faces. Carbon dioxide pressure, additionally, is applied to the backoi thevalve head I16. As long as thispressurecon'dition exists, the valve head I14 willre'rnainagainstits seat and carbon dioxide will be prevented from flowing to the pipe line I63, the pipe I55 and the discharge nozzle I56. However, when the trigger lever I58 is moved toward the grip I49Qthe" pilot valve operating lever I66 isa'ctuated w unseat the valve I68.

When thi's' val ve' is unseated, the chamber of the,

pilot valve casing I61 is vented to the atmosphere and the carbon dioxide pressure is re.

movedfrom the cylinder. I1I of the differential pressure valve casing I54. The carbondioxide pressure applied to the inner face of the piston for'thelvalve member I13 then operates to unseat thevalve head I" and carbon dioxide will then flow through the pipe lines I51, I53, and I55 to the discharge nozzle I56.

As carbon dioxide is admitted to the pipe line I53, it flows'through the short pipe section I15 tothe cylinder I16 formed in the top of the fluid pressure operated valve casing I58a. This carbon dioxide pressure acts on the piston I11 and results inunseating the valve I18 which is normally retained againstits seat by a suitable spring that underlies the same. Water then will be permitted toflow from" the supply tank 33 throughthe pipe lines I51a, I59 and I60 to the water discharge ring I62.

Itnow will be appreciated that the person designated to manipulate the combined carbon dioxide and water discharge mechanism by means of the pistol grip I49, attached to the universally movable barrel I66, may start and stop the flow of carbon dioxide and water by manipulating the trigger-lever I58. Manipulation of this lever results in seating and unseating pilot valve I68. When the pilot valve is unseated, the carbon dioxide and water will flow to their respective discharge devices. When the pilot valveis seated, the flow of both carbon dioxide and 'water will be stopped.

Figs. 10 and 11 clearly show the various control triggerlever I56 andits cord I64 are the only portions of the control mechanism which are located outside of the vehicle body.

Asultable platform I19 7 of the vehicle body and is reached by a suitable ladder I88. the discharge mechanism stands on this platform and manipulates the discharge mechanism when this mobile fire fighting unit is being employed for extinguishing a fire.

Coming now to the disclosure of Figs. 15 to 21.

inclusive, we have a mobile'flre fighting unit which is provided with two booms which may be raised and lowered as well as swung horizontally. The extent to which each boom may be raised and lowered is approximately 90?. The extent to which each boom may be swung horizontally is approximately180".

By referring first to Figs. 15 and is", it wu be seen that a pipe line I8I extends from the bot-I tom portion of the carbon dioxide .st'orage, tank I26 to a manual control valve I which is located outside of the tanlr and its insulation. Just be yond this valve I82,.the pipe line, is formedinto two branches I63 which extend to the respective booms. a A

In Figs. 19 to 21 inclusive there. is shown the will be understood that each boom is mounted in the same manner. Fig. 21 discloses a branch line I83 as being connected to an elbow I8l.whlch.in

turn has connected thereto a short vertical pipe,

section I85. This pipe section I85 has a han I86 ,formed on its upper end. V

A turntable I88 is mounted in an opening formed in the roof portion of the vehicle body Illythat is, in the roof of the drivers cab I810! the vehicle body. This turntable is supported for. angular. movement by a suitable number of rollers I89 which are arranged in a groove. or

trackway I90. The turntable I68 is'formed in two parts so thatthe top and bottom flanges of the groove or trackway I9II'may be separated m admit the rollers I69 The detachable 1 bottom portion I88a of the turntable is provided on its periphery with gear teeth I9'I which are engaged by the teeth of the pinion I92. This pinion is r suitably keyedto an operating shaft I93. which extends through the cab roof and has operating wheels I94 attached to its. upper and lower ends. It will be appreciated that the turntable I88may. berotated either from within the drivers cab It! or from the roof of the vehicle by means of these respective hand wheels I94.

The top flange I86 of the carbondioxide p pe section I is clamped to the upper member of the turntable I88 by means of a ring I95. This ring acts as a swivel mounting for the pipe flange I86. Suitable packing, not shown, will be interposed between the pipe flange and the body of the turntable I88; I I

A pipe nipple. I 91 is threaded into aholeformed in the upper part of the turntable I88 and registers with the carbon dioxide pipe section I85 so that a flowpath for carbon dioxide will be formed by these two pipe sections I85and I91 The pipe section I91 is suitably connected to has been made to disclose packing between these extends across the top The person designatedto operate two half coupling members I98 and I99 but it is to be understood that suitable packing is to be used.

The half coupling member I99 has connected to its outlet branch a pipe 20I which functions as the arm of a boom and as the conduit for the carbon dioxide to be discharged from the outer end of the boom.

To support this boom arm 20I for vertical swinging movement, a fork 202 is connected to the boom arm 20I. The branches 203 of this fork are pivotally connected to the upstanding ears or arms 204 by means of pivot pins 205. These upstanding ears or arms are carried by the turntable I88 so as to move angularly with the latter. It will be appreciated, therefore, that when th turntable is rotated by means of either one of the wheels I94, the associated boom arm 20I will rotate with the turntable.

By referring specifically to Figs. to 18 inclusive, it will be seen that each boom arm I has mounted on its outer end a carbon dioxide discharge nozzle 208. This nozzle is connected to the end of the boom arm by means of another half-together swivel coupling 201 which allows the discharge nozzle to pivot about a horizontal axis at right angles to the boom arm.

To effect and control this pivotal movement of each carbon dioxide discharge nozzle relative to its boom arm, the nozzle has formed thereon mearwardly extending fingers 208 which are connected to control cables 209. These control cables extend longitudinally of their respective boom arm 20I and are connected at their inner ends to the opposite arms of a double lever 2I0. This connection of the inner ends of the control cables 209 to the opposite arms of the double lever. 2I0 is best illustrated in Fig. 18. Figs. 19 and 20 clearly illustrate this double lever 2I0 as being pivotally supported by one of the pivot pins 205 which connects an arm 203 of the yoke 202 with its respective supporting ear 204. This type of support for the double' ended lever 2| 0 causes its axis of pivotal movement to correspond with the axis'of pivotal movement of the associated boom arm 20I. If desired, the bolt 200 for connecting the two half coupling members I98 and I99 may also be employed as the mount for the double ended lever 2I0 and as the pivot pin for connecting the fork arm 203 and the mounting ear 204 on the level side. In any event, the lever 2I0 should be capable of being moved relative to the associated boom 20I so as to tilt the carbon dioxide discharge nozzle 206 relative to its boom while the double ended lever 2I0 should swing with its boom when-the latter is raised or lowered.

Each boom H0 is raised and lowered by means of a cable 2 which is attached at its outer end to the boom at a point intermediate the ends of the latter. This cable 2 extends to and I passes around a sheave 2I2 which is mounted for swiveling movement on the upper end of a standard 2I3 that extends vertically from the roof of the driver's cab. The cable 2 extends through the bore of this standard to the interior of the drivers cab where it passes over a guiding sheave 2I4 and is wound around the spool 2I5 of an electric motor driven winch. This winch may be reversibly driven so that its spool or drum 2I5 will either wind up or unwind the cable 2. The electric motor for each winch is supplied with electricity from the'battery 2I6 of the vehicle by means of wires 2II. A reversing switch 2I8 is mounted in the drivers cab so that the driver, or an attendant, located in the cab may control the operation of the winches for both of the booms. To enable a person located on the top of the vehicle to also control the raising and lowering of the booms, a second motor reversing switch 2I9 is provided for each winch and is mounted on the respective standards 2I3. Figs. 16 and 17 disclose the two standards 2I3 and the bracing bars 220 which interconnect the standards. I

The two carbon dioxide discharge nozzles are provided with water discharge rings 22I of the character disclosed in detail in Fig. 14. These rings are supplied with water through the interconnected hose line 222 and pipe line 223 The two pipe lines 223 for the two water rings are joined together above the water tank 83 and receive their supply through the dip-tube control levers 225 to the operating cams 221 of the pilot valves 228 which are provided for the respective booms. Suitable guiding sheaves 229 are provided for the cables 226. Certain of these sheaves 229 are supported by bracket gfgns 230 which are supported by the standards Coming now to the control valves for the discharge of carbon dioxide and water from the outer end of each boom arm 20I, it is believed that Fig. 18 provides the clearest illustration. The pilot valve unit 228 is provided with a chamber 23l which is normally in communication with the carbon dioxide supply pipe I83 through themedium 'of the tube 232. This chamber 23I, also, is in communication with the cylinder 233 of the differential pressure valve casing 234 through the medium of the tube 235. A spring loaded valve 238 is provided in the pilot valve chamber 23I and is controlled by the cam lever 221. A vent 231 is provided for the pilot valve casing 228 and communication between the chamber 23I and the vent 231 is controlled by means of the valve 236.

With the valve 236 in the position illustrated in Fig. 18, carbon dioxide is delivered from the supply line I83 to the cylinder 233 where the pressure of the same is applied against the upper face of the piston 238. This piston operates to control the seating and unseating of the valve 239. Carbon dioxide pressure additionally is applied to the upper or inner face of the valve 239 and to the opposed or inner face of the piston 238 through communication of the supply line I83 with the inlet of the differential pressure valve casing 234. The outer end of the stem for the valve 236 is pointed at 240 to cooperate with the tapered seat 2 formed at the pilot valve end of the tube 232. This pointed valve stem end functions as a needle valve for controlling the flow of carbon dioxide through the tube 232 intov the chamber 23I.

When the cable 226 for a particular pilot valve is actuated to pivot its cam lever 221, the push rod 242 operated by this cam lever will function to unseat the valve 236 and to seat the needle valve 240. The delivery of carbon dioxide to the chamber of the pilot valve through the tube 232 is stopped and the carbon dioxide in asqasro this chamber, the tube 236 and the cylinder 2 are ventedtothe atmosphere through the outlet 231. when the cylinderfll is vented, the carbon dioxide pressurezapplied to the inner facei. of the piston 238 will function to unseat the 5 valve 238 and allow carbon dioxide to flow. through the differential ,pressure valve casing 234 and on through .therernainder of. the pipe line i83to the boom: associated with this control mechanism. e H I When carbon dioxide is admitted to the pipe line I83 beyond. the'diiferential' pressure valve casing 234, it will flow through the tube 243 to the cylinder .2 of a fluid pressure operated valve casing 245 which is connected in the water flow pipe 223. The carbon dioxide pressure in the cylinder 2 is applied against the piston 246 and results in unseating the valve 2". When this latter valve is unseated, water will now from the storage tank 33 to the discharge ring Hi 0! the associated carbon. dioxide discharge noz- Zle 206. a n

There now has'been explained mechanism for swinging the respective booms irom a position in front of the vehicle body it! to a position where the boom will overlie the roof of the body. Of course, either boom may be stopped in any intermediate position. There, also, has been disclosed mechanismfor raising and lowering each boom and for tilting the combined carbon dioxide'and water discharge mechanism relative to the outer end of the associated boom. This abilityto manipulate the booms and their discharge devices will permit the extinguishing medium to be discharged in any desireddirection with respect to I the mobile me. fighting unit equipped "inthe manner illustrated in Figs. 15 to 21 inclusive. Whenever desired, the discharge of carbon dioxide and water from. the end of either boom may be accomplished by manipulating either of 40 the control levers 225 for that particular boom.

It further will be appreciated that manipulation of both booms and control of the discharge of the extinguishing medium may be accomplished either from a position within the drivers cab i3 or from a position on top of the vehicle body.

It is to be understoodthat the forms of this invention herewith shown and described are'to be taken as preferred examples of the same, and that variousv changes in the shape, size, and arrangement of parts may beresorted to without departing from the spirit of the invention or the scope of thesubloined claims.

Having thusdescribed the invention, I claim;

1. A fire fighting unitcomprising a self-pro-v pelled wheeled body including an enclosing housing and a drivers cab in advance of the housing, an insulated pressure liquid carbon dioxide storage tank within the housing, a mechanical refrigerating device within .the housing and operatively w connected to said tank for lowering the temperature and pressure of the liquid, carbon dioxide, means operating in response to an increase in pressure in the tank for causing therefrigerating device to operateto maintain the liquid in the tank at a desired constant low temperature and pressure, a dirigible discharge device connected to the tankfor discharging. carbon dioxide and mounted on the front portion of the body above the plane of the bodychassis and forward of the drivers cab so that dischargingcarbon dioxide to the front, the side or upwardly of the body will not be interfered with by any portion of the body, and means operable from within, the. driver's cab for adjusting the position of and forcontrolling the flow of carbon dioxide to the discharge device;

2. A the fighting un' Qcomprising "a self-Di c,

pelled wheeled body, an insulated pressure liquid carbon dioxide storage tank of large volumetric capacity "mounted on said body, a mechanical refrigerating device mounted on said body and operativelymonnected tr; said tank for lowering the temperature and pressure of the l i'uuid carbon dioxide in the tank, means operating in response to an increase in pressure in thetank for causing th refrigerating device to operate to maintain the liquid in the tank at a desired-constant low temperature and pressure, a comparatively small water storagegtank'mounted on said body, means for controllably connecting the'vapor space of the carbon dioxide, storage tank with the water storage tank to build up pressure in'said latter tank for expelling the water, and separate pipe 0 lines for effecting discharge of 'thewater and liquid carbon dioxide from theirrespective-tanks' either simultaneously or independently, the rela -v tive volumetric capacities of the carbon dioxide. and water storage tankfs'be'ingsuchthat "the desired vapor pressure for completely expelling the water may be obtained from the-carbon dioxide tank either prior to, duringor after discharge of -all of the liquid carbon dioxide.

3. A fire fighting unit corm'irising'v a self-propelled wheeled body including an enclosing housing and a driver's cab in advance of the housing, an insulated liquid carbon 'fd'i'o'xide storage tank within 'the housing, mechanical refrigerating means withinthe housing'andoperatively connectedto said tank for lowering the temperature and'pressur'e of the liquid carbon dioxide to maintain the same at a desired constantllow temperature and pressure, an adjustabl 'scharg'e device connected to the tank' for disc arging carbon: dioxide and mounted on the frontpor'tion'of the body above the plane of the body. chassis so. that discharging carbon dioxide" to thefront or the side of the body and above the, plane fthebody chassis'will not be interfered with byany portion of the body, and meansoperable fromthe body. of "the unit. for adjusting the position of andfor. controlling the flow of carbon dioxide to the'discharge device/Z v I 1 4. A fire ting unit comprising a self-propelled wheeled body including am enclosing housing and a drivers cab in advance of the housing, an insulated-liquid carbon dioxide-storage tank within the housing, mechanical refrigerating, means within the. housing and operatively. connected to said tank for lowering the temperature and pressure of the liquid carbon dioxide to maintain the same at a desired constant low temperature and pressure, a discharge ,device' con-, nected to the tank for discharging carbon dioxide and adjustablymounted on the front portion of the body so as to be arranged above the plane of the body chassis and so as to discharge carbon dioxide to thefront or the side of the body above the plane of the body chassis without interference from any portion of the body, and means operable from the body of the unit for adjusting the position of and for controlling the fiow of carbon dioxide to the discharge device. 1 i 5. A firefighting unit comprising. a self-propelled wheeled body including an enclosing housing anda driver's. cab in advance of the housing, an insulated liquid carbon dioxide storage tank within thev housing, mechanical refrigerating means within the housing and operatively connected to said tank for lowering the temperature 

